Carbureter for internal-combustion engines.



T. WELSH.

OARBURETER FOR INTERNAL COMBUSTION ENGINES.

APPLICATION FILED JAN. 21, 1910.

. Patented Mar. 5, 1912.

INVENTOR A-& r'Y

WITNESSES do. AM

COLUMBIA PLANMIRAPH CO WASHINGTON, n. c.

TOM WELSH, OF MOFFAT, SCOTLAND.

CARBURETER FOR INTERNAL-COMBUSTION ENGINES.

Specification of Letters Patent.

Patented Mar. 5, 1912.

Application filed January 21, 1910. Serial No. 539,365.

To all whom it may concern:

Be it known that I, ToM WVnLsH, a subject of the King of Great Britain and Ireland, residing at Moft'at, county of Dumfries, Scotland, have invented new and useful Improvements in or Relating to Carbureters for Internal-Combustion Engines, of which the following is a specification.

My said invention relates to oarbureters and has for its object to provide means whereby the inertia of the petrol and air is balanced, in other words to shorten as much as possible the length of the petrol column measured from the jet orifice to the nearest point in the feed system where the petrol communicates with the atmosphere, and to balance the inertia of this column with that of the air. In all spray carbureter-s, hitherto constructed, a comparatively long column of petrol, or other hydrocarbon, is used whose momentum is much greater than that of the air flowing through the carbureter. Consequently when the air flows irregularly through the carbureter less petrol is delivered, per cubic foot of air, than when a regular flow is maintained.

In carrying out my invention a small tube or passage is arranged as near the jet as is possible, the walls of said tube, or passage, consisting of a membrane which is either elastic, or any suitable perforated material may be used, so as to allow the petrol to pulsate to the suction caused by the air flowing over the jet, while at the same time the petrol owing to capillary attraction forms a film on the perforations (where perforated material is used) in the walls of the tube, or passage, and so prevents air passing through the walls of the tube, or passage. A portion of the air passage is made in the form of a cover which can be simply and expeditiously removed when desired.

In order that my said invention and the manner of performing the same may be properly understood I hereunto append a sheet of explanatory drawings to be hereinafter referred to in describing my invention.

Figures 1, and 2, are, respectively, a plan and a transverse section of a carbureter as provided with my improvements. Figs. 3, and 4, respectively, a plan, and a side elevation of parts connected with my improved jet. Fig. 5, is a longitudinal section through the left-hand of Fig. 2, on the dotted line ab, the arrows indicating the direction in which the air flows. Fig. 6 is a transverse section taken on the line 6-6 of Fig. 3.

In these drawings the same reference letters are used to mark the same or like parts wherever they are repeated.

As shown in Figs. 1 and 2, of the drawings the carbureter A, and float chamber B, preferably, consist of a single casting. A triangular passage 0, is formed in the carbureter A, said passage being provided with a detachable cover D, and one of the sides of the passage C, has an opening E, formed in it, said opening communicating with the float chamber B. Within the opening E, there is placed a perforated tube F, which may be composed of wire gauze or the like, the lower end of which is immersed in the petrol in the float chamber B, while the upper end of the tube is fixed to or forms the jet through which the petrol is drawn to the carbureter A. The table F, instead of being constructed as just described, may consist of any suitable elastic or pliable material which will act in the same manner and allow the petrol to pulsate. The opening E, which serves as a reservoir, is open to the atmosphere by means of the passage G. The object of the passage G, is to keep the passage E, open to the atmosphere so that the column of petrol is not unduly extended, in other words, instead of the column as at present being measured from the jet orifice to the nearest point in the feed system (that is the level of the petrol in the tube F) it would be measured as from the level in the float chamber B. Immediately over the jet is placed a small tube, or cover, H, one end of which is inserted in a larger tube, or cover J, the small tube has an opening formed in it to coincide with the jet aperture, and to admit of a spear valve K, passing through it into the jet aperture; The spear valve K, is held in position and adjusted by a nut P. The function of the small tube or cover H, is to insure that only a portion of the total air supply will pass directly over the jet, the tube J, being merely an enlarged extension of the tube'H.

The tubes H, and J, and spear valve K, are, preferably, detachably mounted on a plate L, (also perforated to coincide with the jet aperture) thus facilitating the removal of these parts from the carbureter A. The plate L, may be held in position in any suitable manners In operation the action of my improved jet is as follows :The level of the petrol in the float chamber B, is, as usual, at or about the level of the jet. The petrol rises in the opening or passage E, and also in the perforated tube F, until it reaches about the level in the float chamber B, but owing to the construction of the tube F, the petrol is by capillary attraction drawn up and forms a film on the walls of the tube, from the level of the petrol tothe jet, thus closing the interior of that portion of the tube F, against the action of the air in the passage G. The term air column is intended to mean the distance from the air inlet to the jet, and the term petrol column indicates the distance from the jet to the level of the petrol in the tube F. When the engine is started its suction stroke induces the petrol to flow from the annular passage, or reservoir E, through one or more minute passages to the jet, and by suitably proportioning (as may be found most convenient in practice) the length of the air column between the inlet and the jet, and the length of the column of petrol through the shortest passage from the annular passage or reservoir E, to the jet, the inertia of the I petrol and air is balanced. If, for example,

the air column is about two and a half inches and the petrol column one eighth of an inch, it will be found that the inertia of the air and petrol will approximately balance each other., By this means thorough atomization of the petrol and complete carburation of the air is obtained, and the risk of a gaseous mixture, principally composed .of air, being used, when the engine is running slowly with the throttle open, is eliminated. I A convenient and preferred form of carbureter for use in connection with my improved jet is constructed as follows :The carbureter A, is made with two passages, one passage M, for hot air, and the other passage M for cold air, but both passages communicate with the main passage N, and the hot and cold air passages are controlled in any well known way, so as to pass hot air, cold air, or a mixture of both hot and cold air. A division is formed in the passage N, by the port R, (Figs. 2 and 5) so as to form the passage C, hereinbefore referred to. A portion of the air entering the passage M, flows through the passage C, and a portion of this air is drawn into and through the tube or cover H, and over the jet, while at the same time petrol is drawn from the tube F, through the et and mixes with the air, the mixture flowing through the tube J, into the passage N.

What I claim as my invention is 1. In a device of the class described,'in combination, a carbureter provided with an air passage, said air passage being provided with a jet opening, a float chamber, a tube positioned for conducting the hydrocarbon from the float chamber to the jet opening in said air passage, the portion of said tube adjacent said air passage being above the level of the liquid in the float chamber, said. tube having a wall adapted to permit the hydrocarbon to pass therethrough into the tube and to permit the hydrocarbon to travel to the upper end thereof by capillary attraction, whereby a film is formed upon the upper portion of the tube to prevent air from passing theret-hrough.

2. In a device of the class described, in combination, a carbureter provided with an air passage, said air passage being provided with a jet opening, a float chamber, and a membranous tube for conducting the hyrocarbon from the float chamber to the jet opening in said air passage, the portion of said tube adjacent said air passage being above the level of the liquid in the float chamber.

8. In a device of the class described, in combination, a carbureter provided with an air passage, said air passage being provided with a jet opening, a float chamber, and a conduit of perforated material for conducting the hydrocarbon from the float chamber to the jet opening in said air passage, the

portion of said tube adjacent said air passage being above the level of the liquid in the float chamber.

4:. In a device of the class described, in combination, a carbureter provided with an air passage, said air passage being provided with a jet opening, a float chamber, a membranous tube extending between said chamber and a jet opening in said air passage for conducting the hydrocarbon from the former to the latter, the portion of said tube adjacent said air passage being above the level of the liquid in the fluid chamber, and means within said air passage for causing a portion only of the air passing through said air passage to pass over said jet opening.

5. In a device of the class described, in combination, a carbureter provided with an air passage, said air passage being provided with a jet opening, a float chamber, a membranous tube extending between said chamber and said air passage and communicating with said opening for conducting hydrocarbon from the chamber to the air passage, the portion of said tube adjacent said air passage being above the level of the liquid in the fluid chamber, and a conduit vided with an opening registering with the opening in said passage, whereby a portion only of the air passing through said passage will pass over said opening.

6. In a device of the class described, in combination, a carbureter provided with an air passage, said air passage being provided with a jet opening, a float chamber, a membranous tube extending between said chamber and said air passage and communicating with said opening for conducting hydrocarbon from the chamber to the air passage, the portion of said tube adjacent said air passage being above the level of the liquid in the fluid chamber, a conduit positioned within said air passage and provided with an opening registering with the opening in said passage, whereby a portion only of the air passing through said passage will pass over said opening, and a valve passing through said conduit and operat-ively associated with the opening in said air passage.

7. In a device of the class described, in combination, a carbureter provided with an air passage, a float chamber, a conduit extending between said float chamber and said air passage and a flexible tube positioned within said conduit for conducting the hydrocarbon from the float chamber to the air passage, said conduit being 'in communication wit-h the atmosphere whereby atmospheric pressure will be exerted on the external wall of said flexible tube.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

TOM WELSH.

Witnesses:

JAMES VVHITELAW, FREDERICK PIATT.

Copies of this patent may be )btained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

